This invention relates to an apparatus for reducing axle assembly lubricant temperature by moving the lubricating fluid from the hot central portion of the axle assembly to the typically cooler extremities of the axle assembly where the lubricant temperature may be reduced.
Lubricating fluid within an axle assembly increases in temperature as a result of heat generated from gear inefficiencies, bearing drag, seal drag, and churning losses. High temperatures decrease the useful life of the lubricating fluid and, potentially the useful life of components within the axle. To compound the problem, certain vehicle configurations have minimal air flow over the axle assembly and certain operating conditions may require high axle power transmission, both of which further increase axle lubricant temperatures.
Typically rather complex systems have been employed to cool the lubricating fluid and extend the life of axle components. For example, one system incorporates a separate radiator to cool the axle assembly. However, this design requires that lubricant be pumped to the radiator which adds complexity to the overall axle assembly design.
Axle assemblies incorporating internal braking systems have used helical fins to move lubricating fluid. These systems have been designed to remove heat from the brakes and move the heat toward the central portion of the axle assembly where undesirably hot conditions already exist. Therefore, what is needed is a simple design that removes the heat from the central portion of the axle assembly.